Safety Profile of Ambulatory Prostatic Artery Embolization after a Significant Learning Curve: Update on Adverse Events

Abstract

Background: to report the safety of outpatient prostatic artery embolization (PAE) after a significant learning curve.

Methods: a retrospective bi-institutional study was conducted between June 2018 and April 2022 on 311 consecutive patients, with a mean age of 69 years ± 9.8 (47-102), treated by outpatient PAE. Indications included lower urinary tract symptoms, acute urinary retention, and hematuria. When needed, 3D-imaging and/or coil protection of extra-prostatic supplies were performed to avoid non-target embolization. Adverse events were monitored at 1-, 6-, and 12-month follow-ups.

Results: bilateral PAE was achieved in 305/311 (98.1%). Mean dose area product/fluoroscopy times were 16,408.3 ± 12,078.9 (2959-81,608) μGy.m²/36.3 ± 1.7 (11-97) minutes. Coil protection was performed on 67/311 (21.5%) patients in 78 vesical, penile, or rectal supplies. Embolization-related adverse events varied between 0 and 2.6%, access-site adverse events between 0 and 18%, and were all minor. There was no major event.

Conclusion: outpatient PAE performed after achieving a significant learning curve may lead to a decreased and low rate of adverse events. Experience in arterial anatomy and coil protection may play a role in safety, but the necessity of the latter in some patterns may need confirmation by additional studies in randomized designs.

Keywords: embolization; endovascular procedure; interventional; prostate; prostatic hyperplasia; radiology; therapeutic.

Figure 1

Cases of coil protection of extra-prostatic supplies during PAE and prior to microparticle delivery for safe embolization. (A–C) present a case of coil protection of a pattern B prostatic artery (PA). (A): selective angiography of the right PA on an ipsilateral oblique view, originating from a right accessory internal pudendal artery (APA). Penile arteries are visible at the end of the APA (white arrow) and distally to the prostatic arterial branches (black arrows); the penile bed should be protected from microparticle non-target prostatic embolization (the elective location of occlusion is marked with white asterisks). (B): repeat angiography on ipsilateral oblique view, prior to microparticle delivery, and after a 2 and 3 mm diameter detachable microcoil insertion (white arrow). Penile supply is occluded (penile arteries are no longer opacified) and prostatic vessels are still patent (black arrows). (C): repeat angiography on anteroposterior (AP) view prior to prostatic embolization for confirmation of a full uptake of the right hemi prostate. Penile supply is still occluded. (D,E) present a case of occlusion of an accessory inferior vesical artery (AIVA). (D): selective angiography of the right PA on ipsilateral oblique view. The tip of the microcatheter is inserted in the medial branch of the PA (marked by a black, dotted arrow) and the lateral prostatic branch is marked by a black arrow head. Early reflux is observed in an ipsilateral AIVA (white arrow) originating from the PA, confirming the risk of non-target embolization. (E): repeat angiography on AP view prior to PAE and after the insertion of a 2 mm detachable coil in the AIVA (white arrow). The vesical supply is no longer visible and there is a full uptake of the right hemi prostate. (F,G) present a case of occlusion of rectal and vesical supplies. (F): selective angiography on ipsilateral oblique view of a left prostatic artery, which carries a common trunk with a rectal artery (black arrows), described as pattern C1. There is an associated anastomosis (arterial loop marked by a white, dotted arrow) between the PA and left inferior vesical artery (IVA, white arrow), which needs to be occluded prior to microparticle delivery (elective location marked by white asterisks). (G): repeat angiography on oblique view prior to PAE and after the insertion of 2 mm detachable micro coils in the anastomosis to the IVA (white arrow) and in the rectal artery (black arrow), confirming the occlusion of vesical and rectal supplies.

Figure 2

Patient flowchart. PAE: prostatic artery embolization; LUTSs: lower urinary tract symptoms; AUR: acute urinary retention; IPSS: international prostatic symptoms score; QoL: quality of life; IIEF: international index of erectile function; PVR: post-voiding residue; Qmax: maximum urinary flow.

Figure 3

Distribution in study cohort of the origins of the solitary prostatic arteries according to the different patterns. Types 1 to 5 represent the possible origins of the prostatic artery (PA), according to the Assis classification. The values are presented as a number, n. Patterns A, B, and C1 and C2 correspond to the different intra/extra-prostatic supplies of the prostatic artery in case of a solitary PA (one artery per side, n = 493/622 (79.3%) in this study), according to the Amouyal classification. The values are presented as a number (n) and %.

Figure 4

Distribution in study cohort of the patterns of the solitary prostatic arteries according to the different origins. Patterns A, B, and C1 and C2 correspond to the different intra/extra-prostatic supplies of the prostatic artery in the case of a solitary PA (one artery per side, n = 493/622 (79.3%) in this study), according to the Amouyal classification. The values are presented as number, n. Types 1 to 5 represent the possible origins of the PA, according to the Assis classification. The values are presented as a percentage, %.